Singing drinking songs in Iran might show a clear commitment to a certain folk culture. It would also be an act of crass insensitivity and rudeness to the local population. No, there should not be a law to outlaw the singing of those songs. If someone is stupid enough to go and provoke the locals anywhere, they must expect to face the consequences.
There is no necessity for anyone to sing about the glories of drinking beer among Muslims. I don't think you would find much sympathy for an idiot,who did that,on Mudcat.